Color

#3e51cc

#3e51cc
hex#3e51cc
rgbrgb(62, 81, 204)
hslhsl(232, 58%, 52%)
oklchoklch(0.496 0.19 271)
Closest name: Denim (#1560bd)Relative luminance 0.1127

Colors that go with #3e51cc

Charcoal, Sea Green and Amber lead the list. Each partner is a real named colour with the reason it works — a wheel relationship, a neutral that carries it, or a pairing lifted from a palette or brand system that actually shipped — and every pair opens in the palette tool.

Real palettes that use #3e51cc

Tints & shades

Every swatch is its own page — click any to analyze it.

Harmonies

Complementary

Open in tool →

#ccb93e

#3e98cc · #723ecc

#cc3e51 · #51cc3e

Split-complementary

Open in tool →

#cc723e · #98cc3e

#cc3e98 · #ccb93e · #3ecc72

Contrast

#3e51cc as textRatioAAAA largeAAAFix
Aaon white
6.45:1passpassfail
  • AAA: use #3649c9 as the text (7.11:1)
Aaon black
3.25:1failpassfail
  • AA: use #5e6ed4 as the text (4.66:1)
  • AAA: use #8692df as the text (7.19:1)
  • AA: or shift the background to #d9d9d9 (4.57:1)

Fixes keep hue and saturation and move lightness only, so the suggestion stays on-brand. Ratios are symmetric: the same numbers apply with #3e51cc as the background.

Brands using this color

Fonts for this mood

#3e51cc reads as cool, modern. The font library is tagged with the same vocabulary:

mcpConnect your agent — build around #3e51cc
live endpoint

Point any MCP client at the shared colors endpoint and your agent gets the same engine as this page — direct_palette, edit_direction, check_palette, check_contrast — read-only, no key. Every direction it proposes comes with a /colors/d/… link: open it, lock what you like, paste the link back, and the agent edits rather than re-rolls.

endpointhttps://mcp.brandsweets.com/colors/mcp
claude mcp add --transport http brandsweets-colors https://mcp.brandsweets.com/colors/mcp
try this prompt

analyze #3e51cc and generate a 5-color palette that keeps it as the primary; give me the /palettes/new link

tool url/palettes/new/3e51cc-9c9dc4-df864e-231f2d-e9eef1?lock=0&style=vibrant

Want the agent to remember your picks and write them into a living brand? Create a free BrandSweets workspace.

Machine-readable: color.md